import React, { Component, Fragment } from 'react';
import { CSSTransition } from 'react-transition-group';//css动画组件
import './style.css'

class App extends Component{
    constructor(props){
        super(props);
        this.state={
            show:true
        }
    }

    render(){
        return (
          <Fragment>
              <CSSTransition
                in={this.state.show}
                timeout={1000}
                classNames='fade'
              >
                  <div>hello</div>
              </CSSTransition>
          </Fragment>  
        )
    }
}

export default App;